Interpretation of Egyptian hieroglyphics, begun by J.F. CHAMPOLLION, is virtually complete; the other hieroglyphics are still imperfectly understood. Hieroglyphics are conventionalized pictures used chiefly to represent meanings that seem arbitrary and are seldom obvious. Egyptian hieroglyphics were already perfected in the first dynasty (3110-2884 B.C.), but they began to go out of use in the Middle Kingdom and after 500 B.C. were virtually unused. There were basically 604 symbols that might be put to three uses (although few were used for all three purposes): as an ideogram, as when a sign resembling a tree meant tree; as a phonogram, as when an owl represented the sign m, because the word for owl had m as its principal consonant; or as a determinative, an unpronounced symbol placed after an ambiguous sign to indicate its classification (e.g., an eye to indicate that the preceding word has to do with looking or seeing).

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Hieroglyphics